PLEASE HELP !!!!!!!! prove that segment DE is parallel to segment AB.

Slope of AB = (0 - 0)/(x2 - 0) = 0
Slope of DE = (y1/2 - y1/2) / ((x1 + x2)/2 - (x1/2)) = 0
Both lines has same slopes and equal zero.
Two lines are parallel if their slopes are equal. So AB ║ DE